# Relationship history for MSHA mine 3400369

Current hierarchy: **Pitts Bobby L & Tommy L → Bixby Four Star Sand & Gravel Company → BIXBY FOUR STAR SAND & GRAVEL CO**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Keystone Sand & Gravel Company Of Bixby Inc → BIXBY FOUR STAR SAND & GRAVEL CO; 1950-01-01 to 1987-02-10; source msha-controller-operator-history
- **controller_controls_mine:** Mauney L M → BIXBY FOUR STAR SAND & GRAVEL CO; 1950-01-01 to 1987-02-10; source msha-controller-operator-history
- **controller_controls_operator:** Mauney L M → Keystone Sand & Gravel Company Of Bixby Inc; 1950-01-01 to 1987-02-10; source msha-controller-operator-history
- **operator_operates_mine:** Keystone Sand & Gravel Company Of Bixby Inc → BIXBY FOUR STAR SAND & GRAVEL CO; 1987-02-11 to 1988-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Holmes David P → BIXBY FOUR STAR SAND & GRAVEL CO; 1987-02-11 to 1988-07-10; source msha-controller-operator-history
- **controller_controls_operator:** Holmes David P → Keystone Sand & Gravel Company Of Bixby Inc; 1987-02-11 to 1988-07-10; source msha-controller-operator-history
- **operator_operates_mine:** Bixby Four Star Sand & Gravel Company → BIXBY FOUR STAR SAND & GRAVEL CO; 1988-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Pitts Bobby L & Tommy L → BIXBY FOUR STAR SAND & GRAVEL CO; 1988-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pitts Bobby L & Tommy L → Bixby Four Star Sand & Gravel Company; 1988-07-11 to current/open; source msha-controller-operator-history